Circular friction members are well known in the art and are often used in clutch assemblies. The term clutch assembly as used in the present specification and claims is used as a generic term and includes apparatus such as torque converters in addition to many other xe2x80x9cclutchesxe2x80x9d.
U.S. Pat. No. 5,669,474 discloses the use of a circular friction lining used in a torque converter assembly. This patent also discloses oil grooves defined in the friction lining.
The friction members are often constructed from a paper based friction material having a frictional outer surface.
The generally circular friction member is positioned on one or both sides of a circular support disc, which is normally a metal disc. This overall disk assembly is then positioned within a clutch assembly.
Segmented friction members are also known in the art. A segmented friction member is, for example, shown in U.S. Pat. No. 5,332,075. It is also known in the prior art to provide grooves in the friction lining to serve as paths for a cooling fluid, such as oil. The oil is used to cool the disc assembly. For efficient cooling, the volume of oil must be substantial. At one time in the prior art, the groove depth in the prior art friction members was approximately 25% to 50% of the thickness of the friction member. However, to increase the cooling capacity, it is not unusual to extend the oil groove completely through the friction member. This maximizes the heat transfer from the oil coming in direct contact with the support plate. It has been found that these through grooves in the prior art render the prior art friction member weak and difficult to handle before bonding to a support plate.
With the oil groove extending completely through the prior art friction member, it was often necessary to cut the oil grooves after bonding the prior art friction member to the support plate or in the alternative, to use a separate support member, such as a support ring to hold the pieces of the prior art friction member segments in a proper position before bonding to the support disc or plate. The support rings were removed after bonding.
The present invention is directed to an improved segmented friction member for use in a disc assembly for a wet-running friction clutch. One preferred use is in a torque converter.
The improved segmented friction member is generally circular. The segmented friction member includes a plurality of arcuate segments having opposed ends. The ends are engaged with mating ends of adjoining segments of each segment. Each of the segments defines an elongated oil groove which separates each of the arcuate segments into an outer section and an inner section. An oil groove inlet is in communication with a first end of the elongated oil groove and an oil outlet is in communication with the second end of the elongated oil groove. First and second bridges connect the inner section with the outer section.